Chrysomelas, which is Latin for black and yellow, describes the coloration of this species. They are black or dark brown with yellow blotches. Gopher rockfish (Sebastes carnatus) resemble them very closely, but gophers are brown or dark brown with large pink or whitish blotches. Both species are deep bodied with large head spines.

Black-and-yellow rockfish are distributed from Cape Blanco, Oregon to Isla San Natividad, central Baja California, but they are less common south of San Diego, California. They are demersal (bottom dwelling), usually in water less than 60 ft, although they have also been found at depths up to 120 ft. They are a residential species that inhabit kelp beds and rocky reefs. After establishing residence, the adults are highly territorial and travel no more than 2 km from their home range.

Whole otoliths have been used to age this species to a maximum of 30 yr. Based on a calculated age-length relationship, an 8-in. TL black-and-yellow rockfish is approximately 3-4 years old, and a 10-in. fish is approximately 6 years old, and a 12-in. fish is 10-11 years old. The maximum-recorded total length of this species is 15.3 inches.

In central and northern California waters, males and females reach first maturity at 3 yr old, possibly as old as 4 yr for males and 6 yr for females. Corresponding total lengths range from 5.1 to 9.4 in. TL for males, and 5.3 to 9.6 in. TL for females. Fifty percent of the male population will reach maturity at 3 yr old, between 5.1 and 6.5 in. TL, while half of the female population will reach first maturity between 5.3 and 6.3 in. TL, at 3 or 4 years old

Spawning occurs off California from February through the end of July, with peak spawning in February and March. Female black-and-yellows may be carrying fertilized eggs anytime between October and the end of February. In central California, June is the primary month of first appearance of young-of-the-year in kelp bed areas, and they are usually first observed in the kelp canopy.

Adult black-and-yellows are nocturnal feeders, ambushing their prey between dawn and dusk. Predators of the adults include sharks, dolphins, and seals, while juveniles are prey of birds, porpoises, and fishes, including rockfishes, lingcod, cabezon, and salmon.

Urticina lofotensis is a species of sea anemone in the family Actiniidae. It is commonly known as the white-spotted rose anemone or strawberry anemone.
 
Urticina lofotensis has a smooth, red column with vertical rows of white tubercles. In contrast to other similar species, the tubercles are not adhesive and do not normally attract gravel and shell fragments. There are no acontia with stinging nematocysts protruding through the body wall. The oral disk is plain red and the tapering tentacles are red and have no transverse striations. This is a large sea anemone with a diameter of up to 10 cm (4 in) and 15 cm (6 in) length.

Urticina lofotensis is found in the North Atlantic Ocean and the Pacific coast of North America. It occurs between low water mark and a depth of about 15 m (49 ft). It is found on rocks and pilings, in crevices and gullies and favors exposed habitats with fast moving water.